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Summary of the impact

Oxford's research has helped reduce smoking prevalence and
tobacco-related mortality worldwide.
Our epidemiological studies have documented the varied ways in which
smoking causes death in
many countries, as well as the large benefits of smoking cessation, and
have strongly influenced
the WHO/Bloomberg 2008 MPOWER package, the key document guiding
governmental tobacco
policy worldwide. Oxford University researchers have also coordinated the
systematic reviews that
underpin effective evidence-based policies for encouraging smoking
cessation both in the UK and
worldwide, for example providing evidence supporting NICE guidance for
smoking cessation.

Underpinning research

The underpinning research comes from two departments of UoA2 in Oxford
University. Following
major epidemiological studies of smoking in developed countries in the
1970s and 1980s, the
Nuffield Department of Population Health (NDPH, Peto, Co-Director CTSU)
developed its work
throughout China, showing that smoking was far more important than all
other known causes of
cancer combined. This affected UK, US and Chinese tobacco control
strategies. The families of
one million dead people across China were interviewed to determine the
decedent's smoking
habits and relate them to the disease that caused death, showing that
smoking was already
causing 12% of all deaths in Chinese men [1]. In collaboration with
others, this method of
interviewing families of large numbers of decedents was extended to Hong
Kong (showing that the
epidemic there was at a more advanced stage than in mainland China), to
South India (showing
that smoking was a major cause of death from TB), and then to a random
sample of all adult
deaths in India [2] (showing that the main diseases by which smoking kills
in rural and urban India
are, respectively, TB and heart attacks, and that smoking is causing
almost one million deaths per
year in India alone).

As well as assessing the full hazards of lifelong smoking among men and
among women in many
different populations, retrospective studies of lung cancer and the
50-year results of Richard Doll's
prospective study of smoking and death among male British doctors have
established the lifelong
benefits of cessation at various different ages [3, 4]. Both demonstrated
that stopping smoking
before age 40 avoided more than 90% of the excess risk among those who
continued to smoke.
This epidemiological research has been complemented by the work of the
Cochrane Tobacco
Addiction Review Group (Lancaster, CTARG Director) within the Department
of Primary Health
Care Sciences, Oxford University. Since 1995, CTARG has provided reliable,
regularly updated
summaries of the evidence for interventions designed to help tobacco users
to quit, and to prevent
people from taking up tobacco. The CTARG produces systematic reviews,
including meta-analyses
where appropriate, of individual and population-based interventions for
tobacco control. More than
60 reviews were completed within the reference period.

Examples of this work include:

Systematic review of nicotine replacement therapy (NRT): The
first version of the Cochrane
review assessing the evidence for NRT was published in 1996 and has
grown from 72
studies at inception to over 150 studies now. This work has investigated
different forms,
delivery methods and settings, schedules, and dosages of NRT in a range
of subgroups,
and has shown definitively that all commercially available forms of NRT
increase the
proportion of people able to quit smoking (RR 1.60, 95% CI 1.53 to 1.68)
[5].

Systematic review of physician advice: Despite many doctors'
initial reluctance, physician
advice to quit has become part of everyday practice. The Physician
advice review was first
published in 1996, been updated eight times, and currently includes 41
trials. It shows that
brief clinical advice significantly increases the rate of quitting (RR
1.66, 95% CI 1.42 to
1.94). In addition, the effect was found to be stronger with more
intensive advice [6].

[3]. Peto R, Darby S, Deo H, Silcocks P, Whitley E, Doll R. Smoking,
smoking cessation, and lung
cancer in the UK since 1950: combination of national statistics with two
case-control studies.
BMJ 2000; 321: 323-29. PubMed ID: 10926586. This study combines
data from hospital
patients with and without lung cancer to that from case control
studies from 1950 and
1990 and shows that people who stop smoking before middle age avoid
more than 90%
of the risk attributed to tobacco.

This research was funded by Cancer Research UK and the UK Medical
Research Council.

Details of the impact

Impact on International Policy
Work from UoA2 at Oxford University has provided a spectrum of studies
ranging from
epidemiological evidence of the hazards of smoking through to evidence of
the effectiveness of
quitting and the best available evidence of the success of interventions
that encourage quitting.
These studies have strongly influenced international policy on tobacco
control. In 2008 the WHO
adopted a set of 6 strategic recommendations for tobacco control, which
they refer to as
MPOWER: Monitor tobacco use and prevention policies, Protect people, Offer
help to quit, Warn,
Enforce bans, Raise taxes [A]. Many of the key epidemiological statistics
on tobacco hazards in the
report that defined the MPOWER strategy derive from NDPH work. The central
claim, that during
the 20th Century the tobacco epidemic killed 100 million
worldwide and that during the 21st Century
it will (on current smoking patterns) kill about one billion people, is
derived from NDPH work. The
MPOWER package has, since 2008, been the main vehicle by which WHO has
encouraged
tobacco control.

Similarly, the nicotine replacement therapy for smoking cessation review
(NRT) provided evidence
for a 2008 proposal for the inclusion of NRT in the World Health
Organization (WHO) list of
essential medicines. The WHO reports the review as "the largest database
on the effectiveness of
NRT"[B], approving the proposal in May 2009 supported by
CTARG's "high-quality evidence of
effectiveness" [C]. The WHO website predicts that inclusion of NRT on the
essential medicines list
will advance guideline development and improve access to NRT in developing
countries [C].

Impact on International Guidelines
The CTARG's NRT review has been cited in three key UK national guidelines
in recent years, and
continues to shape practice today. The evidence review [D] underpinning
NICE guidance on Brief
Interventions and Referral or Smoking Cessation recommends the use of NRT
based on the
Cochrane review. Guidelines published from the US and Australia also cite
the review, using it as
consistent evidence for use of NRT to aid smoking cessation and using it
to support the specific
recommendation that heavily dependent smokers use higher doses of oral NRT
[E, F].

Many physicians were initially reluctant to advise patients not to smoke,
as they doubted the
efficacy of the approach and were concerned it would affect the
doctor-patient relationship. The
Cochrane review of physician advice for smoking cessation has been used in
many guidelines as
evidence for the efficacy of this approach. The NICE Rapid Review of Brief
Interventions and
Referral for Smoking Cessation [D], the US Public Health Service
guidelines [E] and the Australian
Royal College of General Practitioner guidelines [F] all cite the review
as evidence that brief advice
from a physician is effective and should form part of routine clinical
care. The Australian guidelines
cite the Cochrane review as the key evidence against the belief that "I am
not effective", one of 7
barriers to engagement of health professionals with smoking cessation
identified by the guideline.

Impact on Smoking Prevalence and Subsequent Mortality
Though the direct relationship between research, subsequent guidelines,
practice, smoking
prevalence (and thereafter mortality) cannot be quantified, both smoking
prevalence and male
mortality have fallen in the UK and in many other European countries
during the REF reference
period. In the 1990's, the decline in UK smoking prevalence that began in
the 1970's had stalled. In
1996, 28% of the adult population smoked and there had been no decline in
prevalence from 1992,
In response, the UK government published its 1998 White Paper `Smoking
Kills' which set out a
range of interventions for reducing smoking prevalence in the UK,
including a substantial
investment in smoking cessation services. This White Paper was based on UK
national guidelines
[I] based on evidence from CTARG's reviews. In the subsequent 14 years,
the prevalence of adult
smoking in the UK has fallen to 20%, with over two million fewer adult
smokers in the UK [G].
Similarly, before the mid-1990s there was no material decrease in EU-wide
tobacco-attributed
mortality, but in recent years male tobacco-attributed mortality in the EU
has decreased by about
10% every 5 years [H].

There is substantial evidence of the impact of the Oxford's UoA2
researchers on the policies that
have been implemented during this period, and the above highlights the use
of selected research
outputs and Cochrane reviews in recent (and current) guidelines and
practice shaping documents.

[B]. 17th Expert Committee on the Selection and Use of Essential
Medicines, World Health
Organization. Proposal for Inclusion of Nicotine Replacement Therapy (NRT)
in the WHO Model
List of Essential Medicines. Geneva: 2008. Page 15 (NRT)http://www.who.int/selection_medicines/committees/expert/17/application/NRT_inclusion.pdf
[Accessed 15/09/2013]. The proposal for inclusion of NRT on the WHO
Essential Medicines
list, which relies heavily on the CTARG's NRT review.